Python: Subprocess Gets a Speed Boost
The Python development team merged 7 pull requests with a standout performance improvement to subprocess.Popen.wait() that eliminates busy-loop polling on Linux, macOS, and BSD systems. The team also fixed a critical mmap error handling bug and resolved Android testing issues, showing great attention to both performance and reliability across platforms.
Duration: PT4M2S
Episode overview
This episode is a short developer briefing from Python.
It explains recent repository work in plain language.
- Show: Python
- Published: 2026-01-29T11:11:38Z
- Audio duration: PT4M2S
Transcript excerpt
This excerpt keeps the crawler page concise. Listen to the episode or use the RSS feed for the full update.
Hey there, Python developers! Welcome back to your daily dose of what's happening in the world of Python development. I'm your host, and wow, do we have some exciting changes to talk about today!
You know that feeling when you're waiting for a subprocess to finish and your code is just... sitting there, checking over and over again if it's done yet? Kind of like asking "are we there yet?" on a long car trip? Well, the Python team just made that a whole lot smarter, and I am genuinely excited to tell you…
Let's dive into today's biggest story - Giampaolo Rodola just merged a fantastic improvement to subprocess.Popen.wait(). This isn't just any small tweak, folks. We're talking about replacing the old busy-loop mechanism with proper event-driven waiting on Linux, macOS, and BSD systems. Instead of your Python process…
Here's what's really cool about this implementation: on Linux systems running version 5.3 or newer, it uses pidfd_open with select.poll, and on macOS and BSD, it leverages kqueue with kernel event filters. The beauty is in the fallback - if these fancy new mechanisms aren't available or something goes wrong, it…
Now, speaking of reliability, we also saw a critical fix…
The…
Nearby episodes from Python
- Threading Race Conditions and Developer Experience Wins
- Small Fixes, Big Impact
- Unpacking Possibilities and JIT Optimizations
- Memory and Performance Powerhouse
- Cleaning Up Our Act - Modern Python Gets a Language Makeover
- Better Error Handling and Quality of Life Improvements
- Security Fixes and Code Cleanup
- Weekly Recap - Memory Safety and Stability Fixes